Project Summary Therapies based on Chimeric Antigen Receptors (CAR) or T Cell Receptors (TCR) have shown incredible potential as personalized immunotherapies for cancer patients which involves enrichment and modification of immune cells to express targeting moieties against cancer cells. Studies have shown that deriving therapies from well-defined sets of cell subpopulations have superior potency and sustained reaction compared to therapies derived from heterogenous populations and represents a direction of growth for the cell therapy industry in order to take on more complex and elusive diseases. Unfortunately, current cell purification platforms, such as flow cytometry and magnetic assisted cell sorting, struggle to balance the throughput and quantitative power needed to precisely enrich the target cell subpopulations for scalable manufacture of precision immunotherapies. We reasoned that a tool that balanced quantitative cell sorting capacity with high throughput operation would alleviate this bottleneck and enable development of more nuanced and multifaceted therapies. With preliminary studies, we demonstrated a prototype platform based on a technique called ratcheting cytometry that can achieve quantitative sorting of target cell subpopulations by multiplexing on magnetic bead strength. In this proposal, we aim to develop a high throughput batch purification cartridge and instrument that can precisely enrich target cell subpopulations directly from complex biomatrix samples, such as a leukopak or apheresis product. In phase I we will focus on optimizing the quantitative separation parameters to maximize capture and purity of multiple target cell types. In phase II we will focus on scaling the platform to meet with cell manufacturing throughput requirements.